Report on the relevance of perovskite module outdoor ageing performance and indoor UV degradation trend.

Perovskite solar cells have made remarkable progress in laboratory-scale efficiency, positioning them as a promising next-generation photovoltaic technology. However, their long-term operational stability under real-world conditions remains a critical barrier to commercial deployment. This study presents a three-year outdoor field investigation of a micro power station composed of 20 perovskite sub-modules (FACsPbI-based, each measuring 30 cm × 40 cm), deployed in subtropical eastern China and fabricated using scalable, industry-compatible processes. The system was continuously monitored over a three-year period to assess its long-term energy output and operational stability under real-world conditions. In parallel, we developed a spectral-accelerated ageing protocol using a tailored ultraviolet to blue-violet light spectrum, with enhanced intensity in the 390-455 nm range. This method enabled a UV dose of 60 kWh m at 65 °C to effectively replicate approximately two years of outdoor degradation. The excellent agreement between the UV-aged and field-aged performance validates this as a practical and predictive tool for evaluating the outdoor lifetime of perovskite modules. The sub-modules demonstrated outstanding durability, with only a 2.83% decline in power conversion efficiency after three years of continuous outdoor operation. These findings support the implementation of perovskite-specific reliability testing frameworks and align with emerging international standards such as IEC TS 63624-1, highlighting the importance of tailored UV protocols in preparing perovskite technologies for commercial deployment.